An integrated circuit (“IC”) is a device (e.g., a semiconductor device) that includes many electronic components, such as transistors, resistors, diodes, etc. These components are often interconnected to form multiple circuit components, such as gates, cells, memory units, arithmetic units, controllers, decoders, etc. An IC includes multiple layers of wiring that interconnect its electronic and circuit components.
Design engineers design IC's by transforming logical or circuit descriptions of the IC's components into geometric descriptions, called layouts. IC layouts typically include (1) circuit modules (i.e., geometric representations of electronic or circuit IC components) with pins, and (2) interconnect lines (i.e., geometric representations of wiring) that connect the pins of the circuit modules. A net is typically defined as a collection of pins that need to be connected. To create layouts, design engineers typically use electronic design automation (“EDA”) applications. These applications provide sets of computer-based tools for creating, editing, and analyzing IC design layouts.
Fabrication foundries (“fabs”) manufacture ICs based on these IC design layouts. To fabricate an IC after designing of the IC layout is completed, a lithographic plate (photomask) is created based on the IC layout so that the photomask contains the various geometries of the IC layout. The various geometries contained on the photomask represent the IC elements (such as IC components, interconnect lines, via pads, etc.) to be created on a wafer in a particular circuit pattern, the wafer forming the base of the integrated circuit.
In some circumstances, some fabs are not able to manufacture ICs based on an IC design layout that is otherwise valid. This is due to the fact that the IC design layout requires certain manufacturing capabilities/settings that the fab does not have. As such, these IC design layouts do not take into account manufacturing constraints. Accordingly, because of these manufacturing constraints, the IC design layout needs to be modified to account for these manufacturing constraints. However, such modifications are made after the IC design layout is designed and sent over to the fabs.
Thus, there is a need in art for a set of computer-based tools that are capable of factoring constraints of the manufacturing process (e.g. lithography process). Similarly, there is a need in art for a set of manufacturing processes that are aware of constraints used to design an IC.